Method and apparatus for treatment of an endless fiber strand or the like

ABSTRACT

There is disclosed a method and apparatus for the treatment of an endless fiber strand by means of at least one gas current serving as a carrier medium, the direction of flow of this gas extending at an angle to the path of movement of the fiber strand, the gas current flowing past a section of predetermined length of the path of travel of the fiber strands. According to the invention a vortex or spin flow is imparted to the gas, the fiber strand being guided so as to pass near the axis yet outside of the core region through the vortex flow.

United States Patent Gasser et al.

[451 Oct. 31, 1972 [72] Inventors: Hermann Gasser, Hansruedi Hotz,

both of Zurich, Switzerland [73] Assignee: Luwa AG, Zurich, Switzerland [22] Filed: July 27, 1970 [211 App]. No.: 58,520

[30] Foreign Application Priority Data July 30, 1969 Switzerland ..11583/69 52 us. c1. ..28/59, 28/62, 34/23, 34/155, 264/348 51 Int. Cl ..D06c 1/06 [58] Field of Search ..28/62, 59, 76; 34/23, 155; 165/2, 58; 264/237, 348; 57/34 B [56] I References Cited UNITED STATES PATENTS 3,425,107 2/1969 Matsui et al. ..28/62 x 3,534,453 10/1970 Lefebure ..57/34 B X 1,576,906 3/1926 Greve ..28/62 2,090,352 8/1937 Herrmann ..34/23 3,425,107 2/1969 Matsui et al. ..28/62 X FOREIGN PATENTS OR APPLICATIONS 2/1962 Great Britain ..28/62 Primary Examiner-Louis K. Rimrodt Attorney-Werner W. Kleeman [57] ABSTRACT There is disclosed a method and apparatus for the treatment of an endless fiber strand by means of at least one gas current serving as a carrier medium, the direction of flow of this gas extending at an angle to the path of movement of the fiber strand, the gas current flowing past a section of predetermined length of the path of travel of the fiber strands. According to the invention a vortex or spin flow is imparted to the gas, the fiber strand being guided so as to pass near the axis yet outside of the core region through the vortex flow.

12 Claims, 2 Drawing Figures PHEN'TED w 3 1 I972 INVENTORS l/I/Vskaaq H BY W J M ATTORNEY METHOD AND APPARATUS FOR TREATMENT OF AN ENDLESS FIBER STRAND OR THE LIKE BACKGROUND OF THE INVENTION The present invention relates to an improved method and apparatus for the treatment of an endless fiber strand or the like.

Different techniques have already become known to the art for treating an endless fiber strand, for instance synthetic yarns, by means of a gas. According to one known technique of this type the yarn is cooled by air after texturizing, while it is still in a highly twisted and heated condition. The cool air serving to set the applied twist flows transverse or lengthwise of the throughpassing yarn.

However, because of the continuously increasing requirements which are placed upon the delivery speed of the yarn from textile finishing machines and the thus resulting reduced treatment times, this type of cooling of the yarn is no longer sufficient in a great many cases.

SUMMARY OF THE INVENTION Accordingly a real need exists in the art for improved method and apparatus for the treatment of an endless fiber strand or the like which is not associated with the aforementioned drawbacks of the prior art techniques and equipment. Therefore, a primary objective of this invention is to provide justsuch improved method and apparatus which effectively fulfils this need.

Another, more specific object of the present invention relates to an improved method of treating a yarn which is compatible with the high delivery demands placed upon modern day textile finishing machines.

Still a further significant object of the present invention relates to an improved method of, and apparatus for undertaking treatment of yarn by providing for heat transfer between a yarn and a gaseous medium in such a way that effective treatment can be carried out even at high throughput or travelling speeds of the yarn.

Yet a further significant object of the present invention relates to an improved apparatus for the treatment of a fibrous strand in a relatively quick, efficient and economical manner, permitting of increased production capacity by virtue of the higher throughput rates which can be employed with the inventive apparatus.

Although it might be considered relatively apparent to carry out the cooling operation through the use of a colder medium than the surrounding or ambient air so as to provide for a more intensified cooling operation to compensate for the shorter treatment times, the invention is based upon the recognition that a more intensive treatment of the fiber strand with a gas current is then possible if the flow of the gas current itself is caused to behave or perform in such a way that the heat exchange can be carried out with considerably improved efficiency while the energy requirements remain practically unchanged or are only slightly increased.

Now, in order to implement the aforementioned objects of the invention, as well as the further objective of attaining as high as possible flow velocities of the gas with the minimum amount of energy consumption,

' while preventing any adverse influence upon the path of the fiber strand in the flow zone by virtue of the high flow velocities, the inventive technique utilizes the steps of imparting a vortex or twist flow to the gas, and

the fiber strand is guided so as-to pass near the axis of the vortex floiw yet externally of the core zone thereof through the vortex current.

By utilizing a vortex flow, and according to a preferred embodiment of the invention, a potential vortex, the fiber strand is guided by the flow current, even though such engages with the surface of the fiber strand at an angle with respect to the axis of the path of travel of the strand or the axis of the strand itself. Any deflection of the fiber strand which may possibly occur out of the predeterminedaxis of the path of travel is therefore without significance as far as the treatment technique is concerned. On the other hand, of particular significance is the fact that flow velocities occur in the potential vortex which are a multiple of the velocity or speed at the inlet or outlet of the flow current in the treatment apparatus. The high flow velocities can be, however, of significance for other techniques than heat exchange.

Furthermore, in order to carry out the heretofore described inventive method the apparatus aspects of the invention contemplates, in accordance with a preferred embodiment, the utilization of a spiral housing. Now for the purpose of generating the potential vortex the air can either be blown tangentially into the spiral housing or can be sucked through an opening into the spiral housing. In the latter case the cross section of the spiral housing, according to a further aspect of a preferred embodiment of the invention, widens conically towards the suction opening of the spiral housing.

The invention will now be described hereinafter with respect to a preferred embodiment of inventive apparatus structure which is utilized for carrying out the inventive technique, for instance for the cooling of a fiber strand by the surrounding air.

BRIEF DESCRIPTION OF THE DRAWING The invention will be better understood and objects other than those set forth above, will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawing wherein:

FIG. 1 is a schematic sectional view of a preferred embodiment of inventive apparatus incorporating a substantially spiral-shaped sleeve or housing utilized for the performance of the inventive method; and

FIG. 2 is a cross-sectional view of the apparatus structure depicted in FIG. 1 taking substantially along the line 11-11 thereof.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS lengthwise opening or slot 14. Furthermore, housing 12 that is the potential vortex can be may remain constant thoughout the length of the housing 12. However, if the slot 14 constitutes the inlet opening for the gaseous medium, then, according to a preferred embodiment of the invention, the cross section of the housing 12 preferably increases in the direction of the opening 15, which in this case then constitutes a suction opening. In the event that this suction opening is not located at an end of housing 12, then the spiral-like housing can also be constructed as a double conical member.

According to a preferred embodiment of the housing structure 12, the opening is preferably arranged at the region of one of the end faces,here shown to be the end face of wall 31. Opening 15 merges with a connecting piece or stud 18 coupled with a suitable source of negative pressure. In this case the vortex or spin flow, generated by sucking air through the slot or opening 14.

A further possibility of producing the potential vortex resides in tangentially blowing air into the sleeve or housing 12 either through the slot 14 or through the slot or opening 14 since'the cross section of the spirallike housing widens in accordance with the quantity of .air increasing in the direction of the withdrawal opening. As a result, the fibrous strand within the housing, for instance when usingthe apparatus at a texturizing machine, can be cooled very quickly and uniformly throughout the entire length of the spiral even in a .highly twisted condition by the air surrounding themachirie.

An even more effective cooling can be obtained if the gas which is used is not only effective because of its temperature, rather also serves as a carrier medium for finally divided or dispersed water droplets for instance,

connecting piece 18. The axis of the connecting piece 18 at the region of the opening 15 extends at an angle to the lengthwise axis of the spiral-like housing 12.

Viewed in the direction of the flowing gas there is arranged in front of the opening 15 a shutter or screening mechanism 20 extending over the cross section of the spiral housing 12, shutter 20 having a central opening 21 and a slot 22 for threading in the fiber strand to be processed. This opening 21 defines a throughflow cross section which'substantially corresponds to the cross section of the core of the vortex formed in the spirallike housing 12.

Housing 12, now to be described more fully, is preferably constructed in such a way that internally thereof there is formed a potential vortex in which the rotational speed increases towards the inside. This potential vortex possesses the aforementioned core or nucleus in which the flow possesses a slight twist and a velocity which is predominately directed inthe axial direction. The fiber strand to be processed preferably passes through the spiral housing at that location where the rotational speed is greatest and the axial speed is still relatively small, this being outside the core zone of the vortex.

It has been found that with a spiral or scroll housing which extends through 360, the best conditions for a rapid heat exchange between the gas and fiber strand prevails approximately at an angle of 90 measured from the slot and at about one third of the spacing from the center of the spiral.

Due to the use of a spiral-housing for the treatment apparatus and especially by virtue of its concial construction, as clearly shown in F IG. 1, there is attained a very uniform suction of air over the entire length of the which favorably influence the heat exchange operation. Furthermore, the chemical and/or the physical properties of the gas can be utilized to increase the heat exchange operation, as for instance the cooling effect which is attained during expansion of Co -gas under certain conditions.

The inventive method and the inventive apparatus cannot only be used for cooling rather also for heating or for influencing the moisture content of a fiber strand. Additionally, it is conceivable to utilize the invention for the application of brightening agents or other agents to the yarn or a thread. Finally, it is here still further to be mentioned that the gas expelled from the housing, following treatment of the fiber strand, can be, if desired, reconditioned and then delivered back into the housing, or else, a fresh supply of gas can be introduced continuously into the housing during the treatment operation while the portion of the gas current previously used during treatment then simply is exthereto but may be otherwise variously embodied and practiced within the scope of the following claims.

Accordingly, What is claimed is:

1. A method for the treatment of an endless fiber strand by means of a gas current serving at least as a carrier medium, comprising the steps of imparting a vortex flow to the gas current, said vortex flow including a core zone of relatively smaller velocity than the remaining zone of the vortex flow about said core zone, moving the endlesss fiber strand in a substantially linear condition through a predetermined path of travel, moving the vortex flow past a section of predetermined length of the path of travel of the fiber strand, guiding the substantially linearly extending fiber strand in a position to move through the vortex flow near and substantially parallel to the axis thereof but externally of the core zone of the vortex flow and at the region of relatively greater velocity of the gas current in order to have as high as possible relative velocity between the gas current and the moving fiber strand to thereby intensify treatment of the endless fiber strand by the gas current.

-2. A method for the treatment of an endless fiber strand as defined in claim 1 wherein the endless fiber strand constitutes a heat-treated yarn which is in highly twisted condition, the gas current being utilized for cooling of such yarn.

3. A method for the treatment of an endless fiber strand as defined in claim 1, including the step of feeding the gas current over the entire length of said section of predetermined length of the path of travel of the 'yarn, and collecting and withdrawing the gas current at one end of said section in a manner that there is formed a potential vortex.

member possessing a substantially spiral-like con-.

figured cross-section, said housing being provided with an inlet opening and a discharge opening for a gaseous medium, one of said openings for said gaseous medium extending approximately over the entire length of said housing and being formed at the outside region of the spiral-like configured housing, said one opening further serving to permit threading-in of the endless fiber strand into the interior of said housing member.

6. The apparatus as defied in claim 5, wherein the cross-section of said spiral-like configured housing varies over its length.

7. The apparatus as defined in claim 5, wherein said one opening extending over the length of said housing constitutes the inlet opening for the gaseous medium and the other opening constitutes the discharge opening for said gaseous medium and is arranged at a boundary wall of said housing.

8. The apparatus as defined in claim 7, wherein a straight line disposed substantially perpendicular to a plane containing said discharge opening forms an angle with respect to the lengthwise axis of said housing.

9. The apparatus as defined in claim 7, further including shutter means arranged in front of said discharge opening-in the direction of flow of said gaseous medium.

10. The apparatus as defined in claim 9, wherein said shutter means possesses an opening defining a throughflow cross section which corresponds to the cross section of the core of the vortex formed in said spiral-like configured housing. 7

11. The apparatus as defined in claim 5, wherein that portion of the gas current used for treating each finite portion of the endless fiber strand as it moves through said predetermined path of travel is continuously replaced by a fresh supply of gas during the treatment operation.

12. The apparatus as defined in claim 5, wherein said housing member includes a respective end wall at opposed ends thereof, said one opening extending between said end walls, each of said end walls having a throughpassage opening for the endless fiber strand, one of said throughpassage openings defining an inlet opening for movement of the fiber strand into said housing member and the other of said throughpassage openings defining an outlet opening for the exit of said fiber strand out of said housing member. 

1. A method for the treatment of an endless fiber strand by means of a gas current serving at least as a carrier medium, comprising the steps of imparting a vortex flow to the gas current, said vortex flow including a core zone of relatively smaller velocity than the remaining zone of the vortex flow about said core zone, moving the endlesss fiber strand in a substantially linear condition through a predetermined path of travel, moving the vortex flow past a section of predetermined length of the path of travel of the fiber strand, guiding the substantially linearly extending fiber strand in a position to move through the vortex flow near and substantially parallel to the axis thereof but externally of the core zone of the vortex flow and at the region of relatively greater velocity of the gas current in order to have as high as possible relative velocity between the gas current and the moving fiber strand to thereby intensify treatment of the endless fiber strand by the gas current.
 2. A method for the treatment of an endless fiber strand as defined in claim 1, wherein the endless fiber strand constitutes a heat-treated yarn which is in highly twisted condition, the gas current being utilized for cooling of such yarn.
 3. A method for the treatment of an endless fiber strand as defined in claim 1, including the step of feeding the gas current over the entire length of said section of predetermined length of the path of travel of the yarn, and collecting and withdrawing the gas current at one end of said section in a manner that there is formed a potential vortex.
 4. A method for the treatment of an endless fiber strand as defined in claim 1, further including the step of continuously replacing by a fresh supply of gas during the treatment operation that portion of the gas current used for treating the endless fiber strand as it moves through said predetermined path of travel.
 5. An apparatus for the treatment of an endless fiber strand by means of a gas current, comprising a housing member possessing a substantially spiral-like configured cross-section, said housing being provided with an inlet opening and a discharge opening for a gaseous medium, one of said openings for said gaseous medium extending approximately over the entire length of said housing and being formed at the outside region of the spiral-like configured housing, said one opening further serving to permit threading-in of the endless fiber strand into the interior of said housing member.
 6. The apparatus as defined in claim 5, wherein the cross-section of said spiral-like configured housing varies over its length.
 7. The apparatus as defined in claim 5, wherein said one opening extending over the length of said housing constitutes the inlet opening for the gaseous medium and the other opening constitutes the discharge opening for said gaseous medium and is arranged at a boundary wall of said housing.
 8. The apparatus as defined in claim 7, wherein a straight line disposed substantially perpendIcular to a plane containing said discharge opening forms an angle with respect to the lengthwise axis of said housing.
 9. The apparatus as defined in claim 7, further including shutter means arranged in front of said discharge opening in the direction of flow of said gaseous medium.
 10. The apparatus as defined in claim 9, wherein said shutter means possesses an opening defining a throughflow cross section which corresponds to the cross section of the core of the vortex formed in said spiral-like configured housing.
 11. The apparatus as defined in claim 5, wherein that portion of the gas current used for treating each finite portion of the endless fiber strand as it moves through said predetermined path of travel is continuously replaced by a fresh supply of gas during the treatment operation.
 12. The apparatus as defined in claim 5, wherein said housing member includes a respective end wall at opposed ends thereof, said one opening extending between said end walls, each of said end walls having a throughpassage opening for the endless fiber strand, one of said throughpassage openings defining an inlet opening for movement of the fiber strand into said housing member and the other of said throughpassage openings defining an outlet opening for the exit of said fiber strand out of said housing member. 